Here the challenge is very similar to https://avishaigonen123.github.io/CTF_writeups/overthewire/natas/natas27.html.

This is the schema we get.

CREATE TABLE IF NOT EXISTS user(   
	id INT NOT NULL AUTO_INCREMENT,
    login VARCHAR(12),
    password CHAR(32),
    PRIMARY KEY (id));

If we’ll create user like: admin [spaces] a, when the a is the 13th char, then it’ll get truncate and when validate, the system will create duplicate to the real admin.

So, we give this:

login=admin       bla&password=11111111

And then can basically login with 11111111

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